Acquisitions and Investment - Purchase Price Consideration Based on Common Stock and Cash Consideration (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Dec. 31, 2013	Nov. 06, 2013 Phygen, LLC [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Fair value of Alphatec common stock issued upon closing		$ 8,856
Cash consideration paid and payable		5,900
Contingent consideration	3,800	3,724
Total purchase price		$ 18,480